The current housing market is dramatically depressed, in that many owners find themselves paying for a home which is worth much less than they paid for it. Such owners search frantically for improvements which have a relatively low purchase, installation and operating cost, whereafter installation they provide a multiplier in improving property value over such cumulative costs. The field of such net value-increase improvements is small. In such a small field, the pressure to reduce purchase, installation or operating costs is intense as home (and even investment and commercial property) owners search for a lowest overall cost for the greatest property value increase.
Among the small field of home improvements which have been found to dramatically affect a purchaser's favorable impression of a home or commercial property is recessed lighting. A properly designed system of recessed lighting can leave undesirable or difficult to decorate areas of a room in relatively low light while focusing a virtually unnoticeable light source on features which a purchaser is likely to desire. Purchase cost of recessed lighting fixtures has plummeted in recent years as high quality, inexpensive import fixtures have become available. However, installation costs have remained relatively high. Part of the installation cost is for professional skill in designing and choosing equipment for a recessed lighting system, which is necessarily time intensive and interactive between the lighting designer and the owner. Making efficient use of this design activity is essential to the owner. A critical aspect of that design process is regularly overlooked. This failure often causes re-design and/or unfavorable actual installation results.
The source of that failure is a necessary part of installation of retrofit recessed lighting. It is well known that original installation and retrofit installation recessed lighting fixtures are so different in design that they are instantly recognizable by those skilled in the art of their installation. Original installation recessed lighting fixtures are intended to be secured between and to parallel ceiling joists or their equivalent ceiling supports for wood planks, wood panels, drywall, sound panels, or other ceiling coverings which hide an underside of a roof or next-story floor from the occupants of a room. The fortunate installers of original installation fixtures can accomplish this installation before the ceiling coverings are put in place.
As such, original installation recessed lighting fixtures are provided with four parallel, extendable arms which extend horizontal to a downward directed “can” or cylindrical body of a housing of a recessed lighting fixture. The arms are extended until their ends abut two parallel ceiling joists, whereafter they are fixed by screws or nails to those support beams. It is left to the installers of the ceiling coverings to provide a circular opening in precisely the correct location so that the downward directed “can” opening is accessible through the ceiling covering. The opening provided in the ceiling covering for recessed lighting has a relatively small tolerance as to diameter and location relative to the “can” opening. A ring-shaped “trim” element provides decorative flashing about a short cylinder which is removably attached to a lower end of the housing in order to cover a space between the edge of the opening in the ceiling covering the lower edge of the “can” that extends near to it. The opening in the ceiling covering must be small enough and located close enough to the lower end of the “can” that the flashing of the “trim” piece can extend substantially farther than the periphery of the opening in the ceiling covering.
In a retrofit circumstance, recessed lighting must be installed entirely through the relatively small opening made in the ceiling covering or panel, which must be identical with the opening that would have been made at an original installation for the same product. Making the opening larger is generally not an economic option. A recessed lighting design typically requires installation of several recessed lighting fixtures in a single room to accomplish the desired lighting effect. First, ceiling covering materials may be of a type that cannot be practically repaired if the opening is made too large, i.e., in the case of wood plank or wood paneling. Second, the cost of repairing a ceiling covering to precisely the texture and coloring of adjacent materials is always difficult or, for some owners, impossible according to their desires. Thus, the retrofit recessed lighting fixture housing and electrical connection structures must be capable of being inserted into an opening of precise circular diameter in a location specific to the lighting effect to be accomplished. Very little variance in the location of the opening is permitted because the lighting effect of a fixture installed offset from a specified position could be visually disturbing and require later major demolition and repair to fix the problem.
While the need for specificity of the location of the openings for recessed lighting fixtures in a unified retrofit design are well known, the locations are generally made without determination of location of studs, joists, pipes, conduit, wires, fiber optic strands, cross-supports, insulation, departures from standard construction, and other structures hidden by the ceiling coverings. If these structures cannot be removed or economically manipulated through a standard retrofit opening to accommodate the installation, the location of the opening must be moved, often to the detriment of the lighting design.
It is well known in the prior art to make a hole one half to one inch in diameter in ceiling coverings to allow visual inspection of a space above the ceiling covering to determine whether there is sufficient space for a retrofit installation. A hole of this size cannot be made at the design stage, in that it cannot be repaired so that it is unnoticeable to the owner. The locations of the retrofit lighting fixtures must have been pre-determined for that reason. An installer must be as certain as possible using sonic or magnetic stud finders as to the location of studs immediately adjacent to the ceiling covering that the recessed lighting fixture. This determination does not provide information about other unseen structures that will prevent installation at a specific site. A device for making retrofit openings is disclosed in U.S. Pat. No. 5,292,210.
The prior art has described devices for finding the distance from a small probe hole to studs within a space behind drywall. The small probe holes are those which would be capable of being repaired to a substantially unnoticeable state after a probe of the hidden space behind the drywall is made. Such devices are disclosed in U.S. Pat. Nos. 2,992,488, 3,274,692, and 4,322,088. These devices suffer from a number of difficulties in actual use. The device of the '488 patent cannot be used with any precision to determine a distance from the probe hole to a stud, in that it cannot be maintained in a precise normal relationship to the exterior drywall surface. Such precision is required for retrofit openings for recessed lighting.
The device of the '392 patent provides for providing assurance that the normal angle is maintained but is limited to finding a stud distance at a single elevation from a rear side of a drywall. Further, it is difficult to maintain in a fully engaged position against an outside surface of the drywall. The device of the '088 patent also suffers from these deficiencies.
There is a need for a device which is capable of determining obstruction of any structure which will interfere with a retrofit installation of a recessed lighting fixture, i.e., in a space hidden behind a ceiling covering which may be intersected with studs, joists, pipes, conduit, wires, fiber optic strands, cross-supports, insulation, departures from standard construction, and other structures hidden by the ceiling coverings.